Concentraciones de radón-222 en el suelo de una zona del cantón Riobamba perpendicular a la Falla Pallatanga

Abstract

The present research project had the objective of quantifying the concentrations of radon-222 in the soil of an area of the canton of Riobamba that is located perpendicular to the Pallatanga fault. A comparative analysis of the soil probe sealing, and the Weeks and Grab protocols was carried out. For this purpose, 32 sampling points were established in the parishes of San Juan, Calpi, and Lizarzaburu. The experimental configuration used in the quantification of radon in the soil consisted of a RAD7 radon gas detector from Durridge Company, which through its front panel, made it possible to configure the Weeks protocol used at each of the 32 sampling points to measure radon222 concentrations. A soft soil gas probe was used to measure radon below ground. 1m depth, which allowed the subsurface gas to be absorbed. The laboratory drying unit was used for fast and efficient drying of the gas, whose filter interrupts the passage of dust particles. As a result, it was identified that the points closest to the Pallatanga fault fluctuated between 2570 to 3930 Bq/m3. Similarly, the highest concentration was observed in Calpi parish (19900 ± 340 Bq/m3) at point R27 approximately 5 km from the fault. The soil sealing with a layer of gypsum is accurate and therefore recommended for soil measurements, whereas the while the Weeks protocol provided a more accurate measurement method. It is concluded, that near the Pallatanga fault there are no high radon concentrations in the soil. Based on this, it is recommended that a detailed survey be carried out at R27 due to the high concentration of radon-222.